4G capabilities, you need to equip it with a SIM card. Our beginners’ tutorial explains where ipad mini sim card slot wont open get the right SIM card, and how to do install it. Phone, you need to buy and install a SIM card.
Information sourced from this Apple support page. This Wikipedia page has more information on the various SIM types, including the much larger full-sized SIM card. However, if you look at quite how massive the full-size SIM is, you’ll realise it would be hard to get them mixed up.